| 摘要 |
<p>PURPOSE: To obtain a fixed number of bits within a narrow limited range per each picture or each picture group by distributing the target value of the number of bits for encoding a supplied picture to plural local target values for each sub-picture, and controlling a step size according to the local target values. CONSTITUTION: An encoding device is provided with a memory 1, and each picture is divided into, for example, 8×8 picture blocks. The prescribed number of continuous blocks are constituted of the four blocks of 8×8 luminance samples and the two blocks of 8×8 chrominance samples. Those blocks are supplied to an encoder 2 constituted of a subtracting circuit 21, picture converter 22, quantizer 23, and variable length encoder 24. The encoder 2 is provided further with a predicting loop for forming a movement compensation prediction picture, and this is constituted of an inverse equantizer 25, inverse picture converter 26, adding circuit 27, picture memory 28, and movement estimator 29. The system of variable length code words thus obtained is constituted of a quantization dependent bit stream 91, and transmitted to a buffer 4, and a channel bit rate (fch) is read.</p> |
